Upstate New York RMH's? And a question on tempered glass...

Hi everyone, I'm new to the rocket stove world but very excited at the prospect. I've been reading up on on rocket mass heaters (RMHs as I'm learning!) and am excited to build one in our new house that we just broke ground on a few weeks ago in Ithaca, NY. I have two questions: Does anyone know of any nearby RMHs I could go to see in person and ask any questions of the owners? I searched the forum and saw two references to upstate NY from Allen Lumley and Thomas Vogel... perhaps one of you is relatively nearby or knows someone who is?

Secondly, the only conceivable "downside" (if you can even call it that) to RMHs versus the traditional wood stoves we were planning on before getting religion was being able to see the fire in the stove. That got me thinking...would it be possible (or maybe ill-advised) to put in some tempered glass in front of the horizontal burn chamber in an RMH so the fire were visible? I know I'd lose a bit of thermal mass there, but, especially since we'll be laying the RMH on a concrete floor that will also collect the heat for subsequent dispersing. Would such a plan be safe? I imagine it would withstand the heat from the chamber...?

We just broke ground, and I won't be putting in the RMH until after we've moved in, but am very excited at the prospect. Thanks much for any advice out there!!

I think Dragon heaters and Walker stoves (builders of RMH that frequent these forums) build stoves with "windows. I'll try to find links.

Yes you can put a glass window or glass door on the end. I am going to do that for my build with a larger burn box.

I'm a partner in Dragon Heaters. Here is our situation on windows. We have implemented 2 different combustion chambers.

The first is a traditional rocket heater with no window; sometimes called a j-tube. The wood is fed vertically into our cast refractory shippable core. This is the most efficient option. We make 3 different sizes of these special cast cores which were designed by Peter van den Berg of the Netherlands.

Peter van den Berg has also designed a batch box which can have a window. This is what Matt Walker is working with. We made some improvements to the gas flow inside the chamber and were just able to start a fire in this new design today. The efficiency is about 88% which is several points lower than what we can get with the j-tube style. Hopefully, a little further tweaking will improve this some.

The batch box design will be much more expensive because of the door and the large casting, etc. than our j-tube product.

Matt Walker and Dragon Heaters are both competing in the Wood Stove Decathalon on the DC mall in a few weeks. His entry is Peter's original design; our entry is our modified one. We proposed Peter's j-tube design, but this entry was eliminated by the judging committee months ago. Consequently, there is no entry in the contest using a j-tube. This competition is being overseen by the Alliance for Green Heat and sponsored by Popular Mechanics.

You would be safest with ceramic glass, not tempered.

What kind of glass is a micro wave dish and door? I downloaded the users manual for the Elm Wildfire wood stoves and they use a standard Pyrex dish for their doors.

Front view of a batch rocket.



Matthew's half barrel J tube with glass.

Wood stoves don't usually get as hot as you can get with a batch rocket, so they don't have to have ceramic glass.

On his website, Matt has a batch box with a window on the side which is cool-looking.

hit mute, and take a look at this glass viewing chamber.

Kartik,
We are East of Cleveland in Ohio. We heat our barn with an 8" RMH with bench, and our house with a downdraft woodstove with a heated cob bench, and we just fired up a portable RMH for greenhouse and display use. We'll be plastering Saturday if you want to come down.

Chris

hey chad iv been loving that video since i stumbled across it a month ago or so.. i have sources a few companies in china that manufacture Quartz glass tubes safe at temps upto 2200F i can get a 6" x 3' peice for about $65 ive been contemplating trying to build one it looks great.